Bicycle-crank



J. J. McGUCKIN.

BICYCLE CRANK.

APPLICATION FILED NOV-Z1, I919.

1,358,225, Patented Nov. 9, 1920.

INVENTOR 5 M Am.

ATTORNEY UNITED m gs THPATENT orricni JOHN J. MCGUCKI N, OF BROOKLYN; NEW YORK, ASSIGNOR T0 LOUIS SC I-I'W'AB, DOING BUSINESS AS STEVEN S & COMPANY, OF NEW YORK, N. Y.

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Be it known that I, J on J. MoGUcmN, a citizen of the United States, residing at No. 3&5 Avenue 0, borough of Brooklyn, county of Kings, city and State of New York, have invented certain new and useful lmprovements in Bicycle-Cranks, of which the following is a specification.

My invention relates to driving cranks for bicycles, and my improvements are par ticularly directed to means for connecting the sprocket wheel to the crank, so that the wheel will be driven by the crank, but can be readily disconnected therefrom and. a new crank or new sprocket wheel of the same or o1. another size may be mounted when desired. Y

The particulars of my invention I will now proceed to point out and claim, refer.- ring, in so doing, to the accompanying drawings in which Figure 1 is a front view of a crank and sprocket wheel embodying my invention; Fig. 2 is a viewo'l the crank looking to the left on Fig. 1, the sprocket wheel being removed; Fig. 3 is a segment of the sprocket wheel; Fig. 4 is a cross sectional view of the crank taken on the line ei-t of Fig. 2 looking up; Fig. 5 is a top view of the stud; Fig. 6 is a side view of the same; Fig. 7 is an edge view of the nut; Fig. 8 i a bottom view of. the stud; and Fig. 9 is a vertical section through the sprocket wheel, showingthe stud permanently attached. Similar parts are designated by the same reference numerals in all the figures.

The shaft 1 is made in the usual form and carries the driving crank 2, having a raised portion 3 in which is formed a groove 4: of a substantially uniform character and extending downward toward the body of the crank 2.

A stud 5 embodies a disk-like head 6, a rib or flange 7, and a shank 8. which may be screw threaded as shown in Fig. 6. The shank of the stud is adapted to enter the hole 10 in the sprocket wheel 11, and to be secured therein by being screw threaded thereinto, or by being held by a nut as 12, or if a permanent connection is desired it may be riveted, as shown in Fig. 9. The

flange 7 is adapted to enter the groove 4 in the crank; and the arrangement of the parts is such that when the cone 13 is screwed up, so as to set the sprocket wheel Specification of Letters Patent.

Application filed November 21, 1919. Serial "No.339,530. i

Pate t Nov. 9; i920.

snugly into place against the hub of the crank 2, the head 6 of the stud will bear against the crank, and its flange? will be securely heldin the groove 4.. U

It has been customary in the art to form a lug orstud integral; withthe crank; and to locate the hole 10 in the sprocketwheel so. as to receive the stud. But in practice the holes 10 in various designs of sprocket wheels are located at diiierent radial distancesfrom the center of the wheel, so that the different sprocket wheels may *not 'be interchangeably used with the same crank, nor vice versa.

My improvement, however, providesadjustable means for connecting the crank and the sprocket wheel, so that although the stud may*e'ngage the sprocketjwheels at varying distances from their centers, it will find a firm bearing in the crank adapted to receive it at any of the positions inthe usual range of variations of the sprocket a crank and a variety of sprocket wheels;

permit the removal and replacement of parts, and, even when the stud 1s permanently secured to a sprocket wheel, as in Fig. 9, another sprocket wheel may be" mounted on the shaft by simply using an other stud.

Obviously my improvements may be modified in detail, as by'the use of mechanical equivalents, .without departing from the spirit oi my invention as claimed.

Having thus described my inventiomwhat I claim and desire to secure byLetters Patent of the United States is:

1 The combination. with a bicycle driving shaft and a crank arm, of a sprocket wheel, and means for preventing relative rotation of the crank arm and sprocket wheel, such means being adapted to engage the crank arm at selectively varied distances from the shaft. 2.. The combination, with a bicycle driv ing shaft and a crank arm, of a sprocket wheel, and a stud constituting means, for

preventing relative rotation of the crank arm and sprocket wheel, such stud being adapted to engage the crank arm at selectively. varied distances from the; shaft,

- tation of the crank arm and sprocket wheel,

such means being adapted; to engage the seat of the crankarm at selective varied dis tances from the shaft. 7

i 4. The combinatio nwith a bicycle sprocket wheel --provided with stud engaging means, a shaft, a crank arm provided with means for engaging a studat varying distances from theshaft, and a cooperating stud having integral means for spacing the sprocket Wheel from the crank arm. a

5. The combination, with a bicycle shaft, and adriving crank providedwith a studbearing constituting means for engaging a sprocket holding stud'at selectively varied distances from the shaft, of either ofa plusaid sprocket wheels and to prevent relative rotation of such crank and wheel,

6, The combination, with a bicycle dr1vcrank provided with a groove constitut V ing a stud bearing, a'sprocket wheel having a stud engaging hole therein, a stud with a neck adapted to be secured in-said hole,an expanded head and a flange upon the head to engage with said groove in the driving crank. I V

7. The combination, witha bicycle shaft and a driving crank provided with means for engaging sprocket holding means at selectively varied distances from the shaft, 0i either of a plurality of sprocket wheels each having a bearing for holding means in a different radial position from-the others, and holding means adapted to cooperate with said crank and with either of said sprocket wheels.

8. A driving crank for bicycles and the like provided with an extended bearing seat for engaging a sprocket holding stud at various radial distances.

JOHN J. MOGUCKIN. 

